The popularity and convenience of the Internet has resulted in the reinvention of traditional telephony services. These services are offered over a packet switched network with minimal or no cost to the users. IP (Internet Protocol) telephony, thus, have found significant success, particularly in the long distance market. In general, IP telephony, which is also referred to as Voice-over-IP (VOIP), is the conversion of voice information into data packets that are transmitted over an IP network. Users also have turned to IP telephony as a matter of convenience in that both voice and data services are accessible through a single piece of equipment, namely a personal computer. The continual integration of voice and data services further fuels this demand for IP telephony applications that support a breath of new services. In addition to the development of new services and features, it is recognized that the traditional telephony services need to be retained.
The Session Initiation Protocol (SIP) has emerged to address the signaling of calls over an IP network. As an end-to-end protocol, SIP advantageously permits the end nodes with the capability to control call processing. By contrast, traditional telephony services are totally controlled by the intermediate network components; that is, the switches have full control over call establishment, switching, and call termination. In the SIP architecture, it is sometimes desirable for an intermediate network element to control the call processing. For example, codec (coder/decoder) incompatibility may require network intervention to ensure that the exchange of packets are meaningful.
Because of the architectural differences between VOIP systems and conventional telephony systems, effecting traditional telephony services, such as music-on-hold, poses a challenge in terms of signaling and efficient use of network resources. The music-on-hold feature provides the party that is placed on hold to listen to a predetermined catalog of music so that the party is aware that the party is on hold.
In a business setting (e.g., call center applications) a caller's willingness to be placed on hold can translate into an increased customer base. The capability for the party to listen to music may have a calming effect so that the party does not grow too impatient during the suspension of the call. In addition to music, a retailer, for example, may place advertisements (or in place of) to alert the party on hold of the products and services that the retailer offers. Therefore, a music-on-hold feature has tremendous commercial value. However, this value is greatly diminished if the cost of implementation is disproportionate.
Therefore, there is a need for an approach for efficiently performing a music-on-hold type feature in a data communications system. There is also a need to preserve a standard architecture to promote deployment of network services, while minimizing system complexity and resources. There is also a need to implement telephony services cost effectively.